This invention relates to a metal casting ladle utilized for casting hot metals, particularly non-ferrous metals such as aluminum and the like. Ladles designed for accommodating casting are well known in the art and have been well developed so that a variety of ladles have been developed for the purpose of addressing specific operating and handling conditions in the art. A problem of particular concern to the industry involved in casting aluminum parts is the corrosive nature of the process.
Ladles made of cast iron and other ferrous metals are commonly used in this industry. Unfortunately, the corrosive nature of the process causes the metal of the ladle to be attacked when exposed to the molten aluminum. In effect, a small amount of the metal from the ladle goes into solution with the molten aluminum. This results over time with a continuous erosion of the metal forming the ladle with the result that ladles need to be replaced on a relatively frequent basis.
A wide variety of manufacturers of metal casting machines also provide a variety of techniques for handling the ladle. Problems which must be solved in the handling of these molten aluminum products involves the proper pouring of the molten aluminum from the ladle as well as filling the ladle with the prescribed quantity of the molten metal. Careful control must be maintained during the handling of the molten aluminum in order to insure that proper casting temperatures are maintained in the transportation of the molten aluminum from the source to the casting mold.
Since there are many manufacturers of machines for handling molten aluminum products, there are likewise many varieties of mechanical arms, transfer booms and similar apparatus adapted to carry the ladle filled with molten aluminum between the source of the molten aluminum and the casting mold. As an example, manufacturers attempt to pour the molten aluminum from the ladle in a controlled fashion. Some manufacturers attempt to carry the ladle in a fashion so that the open top of the ladle is always horizontal.
Other manufacturers solve problems of raising and lowering the filled ladle by a series of sophisticated linkages and pivots in order to insure that spillage and similar accidents will not occur. These transfer machines must be provided with sufficient mobility and operating power in order to direct the ladle over the casting mold without engaging the casting mold or otherwise destroying the mold in the transfer process.
Further, careful control of the rate of flow of the molten metal from the ladle in order to insure high quality moldings constant flow is very important.
As many of these transfer and handling problems have been solved by the various manufacturers, the machine manufacturers have designed machines which employ ladles which may be attached to the machines in a variety of ways. Some machines are designed so that the ladle has a left-hand attachment only. Other machines of the same or other manufacturers are designed to have right-hand attachments to the metal casting ladle. Yet other manufacturers employ ladles which must be mounted with a yoke-type mechanism. The result of these various design adaptations has resulted in a complex and troublesome inventory and use problem for metal casters. The various ways of mounting the casting ladle has required that metal casters maintain a large inventory of ladles designed for a variety of machines employing either left or right-hand attachment of the ladle to the machine.
An additional inventory problem is created by the need to employ ladles having different physical capacities from a few ounces to over twenty pounds of metal. Therefore there is a significant cost incentive for metal castors to reduce the total inventory of ladles necessary to meet the devised casting needs of the various casting needs encountered by a business. This can be achieved by employing a ladle that is adaptable to a wide variety of left and right mount machines and capable of accommodating a variety of mounting brackets.
U.S. Pat. No. 4078707 is a good example illustrating the use of a series of levers and pivots adapted to carry molten metal to a mold where the metal is then poured from the ladle by simply tipping the ladle employing the pivot and lever type arrangements.
Likewise, U.S. Pat. No. 4074837 illustrates a machine employing a series of parallel arms and pivots for the purpose of moving a ladle from a source of molten metal to a casting mold where the metal is deposited from the ladle. Again, it is noted that the device illustrates a complex series of arms which are attached to the ladle for this purpose.
Likewise, U.S. Pat. No. 4353406 also illustrates a machine employing a casting ladle mounted rotatably on a movable support member which conveys a ladle between a filling station and at least one casting station. In this device, the inventor has placed the ladle at the end of an endless chain for manipulating the ladle. The inventor in this patent suggests a device which has a movable support member on which a ladle is mounted for rotation about a horizontal axis which passes substantially through the casting spout. The inventor, however, fails to disclose the mechanisms and the method whereby that is accomplished.